(1) Field of the Invention
My invention refers to a toothbrush, especially constructed to improve dental hygiene when brushing teeth. More particularly, the invented toothbrush may be used as the conventional type toothbrush with several rows of bristles, or converted for use as a single bristle row brush.
It is well known that dentists frequently recommend the use of two toothbrushes, as the regular multirow bristled brush cannot reach into the narrow spaces or crevices between teeth; this is particularly true of the molar teeth, which require diligent care because of their food grinding functions; the molars are not as accessible as e.g., the incissors or canines and, also often provoke a gagging sensation in a person trying to reach the molars with a multirow bristled toothbrush.
An added advantage of having dual levels of bristles is that the user may simultaneously and effectively clean out crevices in and between teeth by applying the single bristled row, and the more accessible portions of the teeth by the lower levelled rows of bristles respectively.
Thus, there appears to be a definite need for a toothbrush, as invented, which can be applied interchangeably as a one or multiple row bristled brush, or as a combination thereof.
(2) Prior Art
The following patents, constituting the most pertinent prior art in light of my disclosure, are listed below.
Havrilla, U.S. Pat. No. 1,592,207, 1926 PA0 Maher, U.S. Pat. No. 726,716, 1903 PA0 Friedman, U.S. Pat. No. 2,326,632, 1941 PA0 Rotceig, U.S. Pat. No. 2,864,111, 1958.
U.S. Pat. No. 1,592,207 depicts a toothbrush wherein some of the bristles may be variously adjusted to alter their length. The effective length of bristles 16 may be changed, i.e., their roots are bent, by sliding auxiliary back 15 as will be evident from an inspection of FIGS. 1 and 4.
U.S. Pat. No. 726,716 discloses a toothbrush which may be cleaned by laterally moving one section with respect to the other sections.
U.S. Pat. No. 2,326,632 illustrates an interchangeable toothbrush and is provided of interest with respect to stem 13 and head 20.
U.S. Pat. No. 2,864,111 relates to toothbrushes "comprising a holder or handle portion having a longitudinal groove therein and a resiliently flexible strip or rod slidable in said groove."